Connecting device with secure mounting

ABSTRACT

Device for connecting one end of a pipe to a bore provided in a fluid transport circuit element, includes a tubular body defining an inner channel for receiving the pipe end, elements for retaining the pipe end in a predetermined axial position in the inner channel and elements for fixing the tubular body in the hole in a predetermined axial position, members for stopping the pipe end mounted on the tubular body designed to be mobile between a projecting position to counter the drive-up of the pipe end to its axial position and a retracted position to clear the passage for the pipe end towards its predetermined axial position, the stop members being designed to co-operate with the element such that they shift from their projecting position to their retracted position when the tubular body is driven in the hole up to its predetermined axial position.

The present invention relates to a coupling device for coupling a pipeend to a bore formed in a fluid transport circuit element. The elementmay be a fluid emitter element such as a pump, or a fluid receiverelement such as another pipe, a tank, . . .

BACKGROUND OF THE INVENTION

A coupling device of this type generally comprises a tubular bodydefining an inner channel for receiving the pipe end. The pipe end isheld in a predetermined axial position in the inner channel of thetubular body by retention means such as a deformable claw washer forbiting into the outside surface of the pipe end or such as a latch thatis movable radially between a projecting position in which the latch canbe engaged behind a collar secured to the pipe end so as to oppose thepipe being withdrawn from the inner channel of the tubular body, and aretracted position in which the latch is disengaged from the collar.

The coupling device further comprises fastener means for fastening thetubular body of the coupling device in the bore of the element in apredetermined axial position. By way of example, the tubular body may bescrewed into the bore of the element or it may be a force-fit therein.If it is a force-fit, the tubular body may be provided on the outsidewith portions in relief, for example, for improving fastening in thebore. The predetermined axial position corresponds to a position inwhich the strength of the fastening is good and/or to a position inwhich the tubular body can co-operate with seals. Such fastener meansare dissociated from the retention means such as a claw washer or aradially-movable latch, i.e. these means operate independently and apipe end can be retained in the tubular body even though the tubularbody is not properly fastened in the bore. When the fastener means forfastening the tubular body in the bore are dissociated from the meansfor retaining the pipe end in the tubular body, there are, at present,no means for verifying that the tubular body is correctly mounted in thebore of the circuit element, other than visual inspection. This leads toa risk that an operator might fail to observe that the tubular body hasnot been correctly mounted. When the circuit is put under pressure,there will then be a risk of leakage, and more dangerously, of thetubular body being expelled from the bore (whiplash effect).

OBJECTS AND SUMMARY OF THE INVENTION

There therefore exists a need that has not been solved in convenientmanner in the past for a coupling device of the above-specified typethat can be mounted in a manner that is secure.

To this end, the invention provides a device for coupling a pipe end toa bore provided in a fluid transport circuit element, the devicecomprising a tubular body defining an inner channel for receiving thepipe end, retention means for retaining the pipe end in a predeterminedaxial position in the inner channel, and fastener means for fasteningthe tubular body in the bore in a predetermined axial position, thetubular body fastener means being separate from the pipe-end retentionmeans. Abutment means for coming into abutment with the pipe end aremounted on the tubular body so as to be movable between a position inwhich they project into the inner channel so as to oppose entry of thepipe end as far as its predetermined axial position, and a retractedposition so as to disengage the passage for the pipe end to go towardsits predetermined axial position, and the abutment means are arranged toco-operate with the circuit element in such a manner as to pass fromtheir projecting position to their retracted position when the tubularbody is pushed into the bore as far as its predetermined axial position.

Thus, so long as the tubular body is not placed correctly in the bore ofthe circuit element, the pipe end cannot be engaged in the inner channelall the way to its predetermined axial position and it therefore cannotbe secured to the tubular body. The impossibility of making theconnection thus constitutes a warning signal to the user that thetubular body is not properly in place.

In a particular embodiment, the abutment means comprise at least onetongue having an end connected to the tubular body so as to beelastically deformable between a deformed state in which the tongue hasa free end projecting into the inner channel, and a rest state in whichthe tongue has its free end retracted.

In which case, the tongue is advantageously provided with a projectionadjacent to its free end and projecting towards the outside of thetubular body to co-operate with a surface of the bore, the bore having asetback for receiving the projection when the tubular body is in itspredetermined axial position.

If the tubular body is not correctly mounted in the circuit element boreand a pipe end is introduced into the tubular body, the movement ofintroducing the pipe end into the inner channel brings the pipe end intocontact with the free end of the tongue so that if the movementintroducing the pipe end is continued, then the pipe end drives thetubular body into the bore until the projection comes into register withthe setback in the bore. The free end then returns to its rest state inwhich it is retracted out from the inner channel, thereby disengagingthe passage for the pipe end towards its predetermined axial position.

Also preferably, the projection possesses a radial surface forming ashoulder for co-operating with a corresponding radial surface of thesetback and opposing a force tending to extract the tubular body fromthe bore.

The projection thus enables the tubular body to be fastened in the boreby snap-fastening.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics and advantages of the invention appear on readingthe following description of a particular and non-limiting embodiment ofthe invention.

Reference is made to the accompanying drawings, in which:

FIG. 1 is a perspective view in longitudinal section of a couplingdevice of the invention;

FIG. 2 is view analogous to FIG. 1 showing a coupling device incorrectlymounted while a pipe end is being introduced therein; and

FIG. 3 is a view analogous to FIG. 2 showing the coupling device oncethe pipe end has been inserted therein.

DETAILED DESCRIPTION OF THE INVENTION

With reference to the figures, the coupling device described herein isfor enabling a connection to be made between a pipe end provided with anoutside collar 2 and a bore 3 of a fluid transport circuit element 4,such as a fluid receiver element like a tank or a fluid emitter elementlike a pump.

The bore 3 opens to the outside via two consecutive chambers ofincreasing diameter, namely an intermediate chamber 5 and an entrychamber 6. A shoulder 7 forms the transition between the entry chamber 6and the intermediate chamber 5, and a shoulder 8 forms the transitionbetween the intermediate chamber 5 and the nominal section of the bore3. The bore 3 includes two setbacks formed by diametrically-oppositeslots 9 formed in the entry chamber 6 to open to the outside of theelement 4.

The coupling device of the invention comprises a tubular body givenoverall reference 10 which defines an inner channel 11 for receiving thepipe end 1 and which possesses an end 12 via which the tubular body 10is designed to be introduced into the bore 3 of the element 4, and anopposite end 13 via which the pipe end 1 is to be introduced into theinner channel 11.

The end 12 is fitted with a bushing 14 which forms a support for seals15 and 16 (O-rings) of inside diameter corresponding to an outsidediameter of the pipe end 1 and of outside diameter corresponding to aninside diameter of the bushing 14 itself corresponding substantially toan outside diameter of the end 12 of the tubular body 10 and to aninside diameter of the intermediate chamber 5. The bushing 14 has anoutside diameter corresponding to an inside diameter of the entrychamber 6. The bushing 14 is connected to the end 12 of the tubular body10 by a breakable connection (a breakable web) which breaks under anaxial compression force.

The end 13 of the tubular body 10 is shaped to contain a latch in theform of a ring 17 which, in conventional manner, forms a retractabletransverse obstacle for the outer collar 2 on the pipe end 1. The bodyend 13 thus includes a chamber 18 into which the inner channel 11 opensout and serving to receive the ring 17 which, at rest, is urged byresilient tabs (not shown in the figures) so that the ring 17 is shiftedto lie off the axis of the inner channel 11. The innermost portion ofthe chamber 18 forms a housing for the collar 2 on the pipe end 1 and inwhich it is held axially by the ring 11 when in its rest state, therebydefining an axial retention position for the pipe end 1 in the innerchannel 11 (see FIG. 3). It will be understood that when the collar 2goes past, the ring 17 retracts (downwards in the figures) because of acamming slope 19 so as to lie on the axis of the inner channel 11, andthen returns to its rest position under drive from the resilient returntabs after the collar 2 has gone beyond the ring 17. In order to unlockthe coupling device, the operator needs to press on the ring 17 againstthe resilient tabs so as to release the collar axially from the chamber18.

The tubular body 10 also comprises abutment means for the terminal faceof the pipe end 1. These abutment means comprise two tongues 20extending axially in the tubular body in diametrically-oppositepositions and each having one end 21 connected to the tubular body 10and an opposite end 22 that is free. The tongues 20 are elasticallydeformable between a deformed state in which the free ends 22 projectinto the inner channel 11, and a rest state in which the free ends 22are retracted. The tongues 20 are provided beside their adjacent ends 22with respective projections 23 projecting towards the outside of thetubular body 10. The distance between the projections 23 is greater thanthe inside diameter of the entry chamber 6 when the tongues 20 are intheir rest state, and is substantially equal to the inside diameter ofthe entry chamber 6 when the tongues 20 are in their projecting state.

At its rearward end relative to the insertion direction of the tubularbody 10 into the bore 3, each projection 23 possesses firstly a radialsurface 24 to constitute a shoulder for co-operating with acorresponding radial surface 25 of the slot 9 so as to oppose a forcetending to extract the tubular body 10 from the bore 3, and at its frontend, it possesses secondly a sloping surface forming a ramp 26 forco-operating with the edge of the entry chamber 6 of the bore 3 so as tobring the tongue 20 into its deformed state (which edge may also bechamfered in order to make this co-operation easier). The slots 9 andthe projections 23 thus form means for fixing the tubular body in thebore 3 by snap-fastening.

The coupling device is assembled to the element 4 by snap-fastening thetubular body 10 in the bore 3 of the element 4. The tubular body 10 isintroduced into the bore 3 via its end 12 in such a manner that theramps 26 of the projections 23 come into contact with the edge of theentry chamber 6 of the bore 3 in the element 4 and cause the tongues 20to be deformed away from their rest state towards their deformed state.The free ends 22 of the tongues 20 then project into the inner channel11. In FIG. 2, it can be seen that if the pipe end 1 is engaged in thetubular body 10 at this stage, then its terminal face comes intoabutment against the free ends of the tongues 20. The distance betweenthe free ends 22 and the ring 17 is shorter than the distance betweenthe collar 2 and the terminal face at the pipe end 1 so that it is notpossible for the pipe to be retained by the ring 17 so long as thetongues 20 are in their deformed state. The operator is thus informedthat the tubular body 10 has been incompletely mounted in the bore.

With continued movement introducing the tubular body 10 into the bore 3(under drive from the operator handling either the tubular body 10itself when the pipe end 1 is not engaged therein, or else the pipe end1 pressing against the free ends 22 during introduction of the pipe intothe tubular body 10), the projections 23 come into register with theslots 9 so that the tongues 20 can return elastically to their reststate. The projections 23 received in the slots 9 then oppose any forcetending to extract the tubular body 10 from the bore 3, thus definingthe axial position in which the tubular body 10 is secured in the bore3. Means can be provided for indexing the tubular body 10 relative tothe bore 3 so as to ensure that the projections 23 are in alignment withthe slots 9 when the tubular body 10 reaches the axial position in whichit is to be secured. Otherwise, the projections can be put into registerwith the slots 9 by turning the tubular body 10 in the bore 3. Inaddition, the slots 9 may be replaced by a groove, thus avoiding theneed to provide any indexing.

During the movement of introducing the tubular body 10 into the bore 3,the bushing 17 becomes detached on encountering the shoulder 8 and ismoved onto the end 12. In this state, the intermediate chamber 5receives the two O-rings 15 and 16.

In FIG. 3, the pipe end 1 is shown secured inside the tubular body 10and engaged in the inner channel 11 thereof. The length of the pipe end1 extending beyond the collar 2 is such that the pipe end 1 in itsretention position inside the tubular body 10 reaches the O-rings 15 and16.

It will also be observed that the slots 9 constitute setbacks givingaccess to the projections 23 and, in the absence of a pipe end 1 engagedin the tubular body 10 they make it possible with a suitable tool topush in the projections 23 so as to allow the tubular body 10 to beextracted from the bore 3.

Naturally, the invention is not limited to the embodiment described andvarious embodiments can be provided without going beyond the ambit ofthe invention as defined by the claims.

In particular, fastener modes other than snap-fastening can beenvisaged.

Furthermore, the fastening means may be separate from the abutmentmeans.

In addition, the invention also relates to devices that are the resultof inverting the configuration of the device described.

Furthermore, the retention means may be different from those describedand may comprise, for example, a claw washer disposed downstream fromthe abutment means so that the abutment means prevent or open access forthe pipe end to the washer depending on whether they are in theirprojecting position or in their retracted position.

1. A device for coupling a pipe end (1) to a bore (3) provided in afluid transport circuit element (4), the device comprising a tubularbody (10) defining an inner channel (11) for receiving the pipe end,retention means (17) attached to the tubular body for retaining the pipeend in a predetermined axial position in the inner channel, and fastenermeans (23) attached to the tubular body for fastening the tubular bodyin the bore in a predetermined axial position, the tubular body fastenermeans being independent from the pipe-end retention means, whereinabutment means (22) for coming into abutment with the pipe end aremounted on the tubular body so as to be movable between a position inwhich they project into the inner channel so as to oppose entry of thepipe end as far as its predetermined axial position, and a retractedposition so as to disengage the passage for the pipe end to go towardsits predetermined axial position, and wherein the abutment means (22)are arranged to co-operate with the circuit element in such a manner asto pass from their projecting position to their retracted position whenthe tubular body is pushed into the bore as far as its predeterminedaxial position.
 2. A device according to claim 1, in which the abutmentmeans comprise at least one tongue (20) having an end (21) connected tothe tubular body (10) so as to be elastically deformable between adeformed state in which the tongue has a free end (22) projecting intothe inner channel (11), and a rest state in which the tongue has itsfree end retracted.
 3. A device according to claim 2, in which thetongue (20) is provided with a projection (23) adjacent to its free end(22) and projecting towards the outside of the tubular body (10) toco-operate with a surface of the bore (3), the bore having a setback (9)for receiving the projection when the tubular body is in itspredetermined axial position.
 4. A device according to claim 3, whereinthe projection (23) possesses a radial surface (24) forming a shoulderfor co-operating with a corresponding radial surface (25) of the setback(9) and opposing a force tending to extract the tubular body (10) fromthe bore (3).
 5. A device according to claim 3, wherein the setback isformed by a slot (9) opening to the outside of the element (4) so as togive access to the projection (23) from outside the element.
 6. Acoupling device according to claim 5, in which the tubular body (10)possesses an end (12) for insertion into the bore (3), which end isextended by at least one seal (15, 16) by means of a cylindrical support(14) temporarily projecting from said end, the seal being arranged, inoperation, to provide sealing between the circuit element (4) and thepipe end (1).
 7. A device according to claim 6, in which the cylindricalsupport of the seal (15, 16) is formed by a bushing (14) connected tothe above-mentioned end of the tubular body (10) by breakable means soas to be capable of retracting around said end of the tubular body whenthe tubular body is mounted in the bore of the circuit element.